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VLSI Design Flow / ASIC Desgn Flow

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 VLSI Design Flow In VLSI (very-large-scale-integration) circuits designing process is highly complex. It is divided into several blocks of designing. The flow of the chip design is shown below. This flow is also called as ASIC (application specific integrated circuit) flow. Earlier steps are high-level; later design steps are at lower level abstraction. At the end of the process, before element's geometric shape and electrical properties. The steps of the VLSI design flow are discussed in detail below. For further reading on physical design algorithms. System Specification.   Chip architects, circuit designers, product marketers, operation managers, and layout and library designers collectively define the overall goals and high-level requirements of the system. These goals and requirements span functionality, performance, physical dimensions and production technology. Architectural Design. A basic architecture must be determined to meet the system specifications. Example...

OVERVIEW OF PHYSICAL DESIGN

Physical Design.   During physical design, all design components are instantiated with their geometric representations. In other words, all macros, cells, gates, transis tors, etc., with fixed shapes and sizes per fabrication layer are assigned spatial loca tions (placement) and have appropriate routing connections (routing) completed in metal layers. The result of physical design is a set of manufacturing specifications that must subsequently be verified.  Physical design is performed with respect to design rules that represent the physical limitations of the fabrication medium. For instance, all wires must be a prescribed minimum distance apart and have prescribed minimum width. As such, the design layout must be recreated in ( migrated to) each new manufacturing technology. Physical design directly impacts circuit performance, area, reliability, power, and manufacturing yield. Examples of these impacts ...